A review on moisture re-adsorption of lignite treated using different drying techniques

Lignite has great potential for use as one of the major sources for both energy and chemical feedstock. However, its high moisture content extremely restricts its use. The moisture re-adsorption of the dehydrated lignite has been studied increasingly in recent years. This review focuses on the issue of the high moisture re-adsorption capacity of lignite dehydrated using various drying techniques. Experimental and simulative studies on the effects of oxygen-containing functional groups, pores, and other factors on the moisture re-adsorption of the dehydrated lignites from different countries or districts and exploratory work on inhibiting the moisture re-adsorption of the dehydrated lignite are reviewed in detail. Of particular interest is a proposal for a mechanism of moisture re-adsorption on the dehydrated lignite. Additionally, future investigations on inhibiting the moisture re-adsorption of the dehydrated lignite are advised.